selftests: Add nettest

Add nettest - a simple program with an implementation for various networking
APIs. nettest is used for tcp, udp and raw functional tests for both IPv4
and IPv6.

Point of this command versus existing utilities:
- controlled implementation of the APIs and the order in which they
  are called,
- ability to verify ingress device, local and remote addresses,
- timeout for controlled test length,
- ability to discriminate a timeout from a system call failure, and
- simplicity with test scripts.

The command returns:
  0  on success,
  1  for any system call failure, and
  2  on timeout.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 1757 insertions, 1 deletions

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 1b24e36b4047..ba9ee36c9e94 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -12,7 +12,7 @@ TEST_PROGS += udpgro_bench.sh udpgro.sh test_vxlan_under_vrf.sh reuseport_addr_a
 TEST_PROGS += test_vxlan_fdb_changelink.sh so_txtime.sh ipv6_flowlabel.sh
 TEST_PROGS += tcp_fastopen_backup_key.sh
 TEST_PROGS_EXTENDED := in_netns.sh
-TEST_GEN_FILES =  socket
+TEST_GEN_FILES =  socket nettest
 TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy reuseport_addr_any
 TEST_GEN_FILES += tcp_mmap tcp_inq psock_snd txring_overwrite
 TEST_GEN_FILES += udpgso udpgso_bench_tx udpgso_bench_rx ip_defrag
diff --git a/tools/testing/selftests/net/nettest.c b/tools/testing/selftests/net/nettest.c
new file mode 100644
index 000000000000..9278f8460d75
--- /dev/null
+++ b/tools/testing/selftests/net/nettest.c
@@ -0,0 +1,1756 @@
+// SPDX-License-Identifier: GPL-2.0
+/* nettest - used for functional tests of networking APIs
+ *
+ * Copyright (c) 2013-2019 David Ahern <dsahern@gmail.com>. All rights reserved.
+ */
+
+#define _GNU_SOURCE
+#include <features.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <linux/tcp.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <errno.h>
+
+#ifndef IPV6_UNICAST_IF
+#define IPV6_UNICAST_IF         76
+#endif
+#ifndef IPV6_MULTICAST_IF
+#define IPV6_MULTICAST_IF       17
+#endif
+
+#define DEFAULT_PORT 12345
+
+#ifndef MAX
+#define MAX(a, b)  ((a) > (b) ? (a) : (b))
+#endif
+#ifndef MIN
+#define MIN(a, b)  ((a) < (b) ? (a) : (b))
+#endif
+
+struct sock_args {
+	/* local address */
+	union {
+		struct in_addr  in;
+		struct in6_addr in6;
+	} local_addr;
+
+	/* remote address */
+	union {
+		struct in_addr  in;
+		struct in6_addr in6;
+	} remote_addr;
+	int scope_id;  /* remote scope; v6 send only */
+
+	struct in_addr grp;     /* multicast group */
+
+	unsigned int has_local_ip:1,
+		     has_remote_ip:1,
+		     has_grp:1,
+		     has_expected_laddr:1,
+		     has_expected_raddr:1,
+		     bind_test_only:1;
+
+	unsigned short port;
+
+	int type;      /* DGRAM, STREAM, RAW */
+	int protocol;
+	int version;   /* AF_INET/AF_INET6 */
+
+	int use_setsockopt;
+	int use_cmsg;
+	const char *dev;
+	int ifindex;
+	const char *password;
+
+	/* expected addresses and device index for connection */
+	int expected_ifindex;
+
+	/* local address */
+	union {
+		struct in_addr  in;
+		struct in6_addr in6;
+	} expected_laddr;
+
+	/* remote address */
+	union {
+		struct in_addr  in;
+		struct in6_addr in6;
+	} expected_raddr;
+};
+
+static int server_mode;
+static unsigned int prog_timeout = 5;
+static unsigned int interactive;
+static int iter = 1;
+static char *msg = "Hello world!";
+static int msglen;
+static int quiet;
+static int try_broadcast = 1;
+
+static char *timestamp(char *timebuf, int buflen)
+{
+	time_t now;
+
+	now = time(NULL);
+	if (strftime(timebuf, buflen, "%T", localtime(&now)) == 0) {
+		memset(timebuf, 0, buflen);
+		strncpy(timebuf, "00:00:00", buflen-1);
+	}
+
+	return timebuf;
+}
+
+static void log_msg(const char *format, ...)
+{
+	char timebuf[64];
+	va_list args;
+
+	if (quiet)
+		return;
+
+	fprintf(stdout, "%s %s:",
+		timestamp(timebuf, sizeof(timebuf)),
+		server_mode ? "server" : "client");
+	va_start(args, format);
+	vfprintf(stdout, format, args);
+	va_end(args);
+
+	fflush(stdout);
+}
+
+static void log_error(const char *format, ...)
+{
+	char timebuf[64];
+	va_list args;
+
+	if (quiet)
+		return;
+
+	fprintf(stderr, "%s %s:",
+		timestamp(timebuf, sizeof(timebuf)),
+		server_mode ? "server" : "client");
+	va_start(args, format);
+	vfprintf(stderr, format, args);
+	va_end(args);
+
+	fflush(stderr);
+}
+
+static void log_err_errno(const char *fmt, ...)
+{
+	char timebuf[64];
+	va_list args;
+
+	if (quiet)
+		return;
+
+	fprintf(stderr, "%s %s: ",
+		timestamp(timebuf, sizeof(timebuf)),
+		server_mode ? "server" : "client");
+	va_start(args, fmt);
+	vfprintf(stderr, fmt, args);
+	va_end(args);
+
+	fprintf(stderr, ": %d: %s\n", errno, strerror(errno));
+	fflush(stderr);
+}
+
+static void log_address(const char *desc, struct sockaddr *sa)
+{
+	char addrstr[64];
+
+	if (quiet)
+		return;
+
+	if (sa->sa_family == AF_INET) {
+		struct sockaddr_in *s = (struct sockaddr_in *) sa;
+
+		log_msg("%s %s:%d",
+			desc,
+			inet_ntop(AF_INET, &s->sin_addr, addrstr,
+				  sizeof(addrstr)),
+			ntohs(s->sin_port));
+
+	} else if (sa->sa_family == AF_INET6) {
+		struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
+
+		log_msg("%s [%s]:%d",
+			desc,
+			inet_ntop(AF_INET6, &s6->sin6_addr, addrstr,
+				  sizeof(addrstr)),
+			ntohs(s6->sin6_port));
+	}
+
+	printf("\n");
+
+	fflush(stdout);
+}
+
+static int tcp_md5sig(int sd, void *addr, socklen_t alen, const char *password)
+{
+	struct tcp_md5sig md5sig;
+	int keylen = password ? strlen(password) : 0;
+	int rc;
+
+	memset(&md5sig, 0, sizeof(md5sig));
+	memcpy(&md5sig.tcpm_addr, addr, alen);
+	md5sig.tcpm_keylen = keylen;
+
+	if (keylen)
+		memcpy(md5sig.tcpm_key, password, keylen);
+
+	rc = setsockopt(sd, IPPROTO_TCP, TCP_MD5SIG, &md5sig, sizeof(md5sig));
+	if (rc < 0) {
+		/* ENOENT is harmless. Returned when a password is cleared */
+		if (errno == ENOENT)
+			rc = 0;
+		else
+			log_err_errno("setsockopt(TCP_MD5SIG)");
+	}
+
+	return rc;
+}
+
+static int tcp_md5_remote(int sd, struct sock_args *args)
+{
+	struct sockaddr_in sin = {
+		.sin_family = AF_INET,
+	};
+	struct sockaddr_in6 sin6 = {
+		.sin6_family = AF_INET6,
+	};
+	void *addr;
+	int alen;
+
+	switch (args->version) {
+	case AF_INET:
+		sin.sin_port = htons(args->port);
+		sin.sin_addr = args->remote_addr.in;
+		addr = &sin;
+		alen = sizeof(sin);
+		break;
+	case AF_INET6:
+		sin6.sin6_port = htons(args->port);
+		sin6.sin6_addr = args->remote_addr.in6;
+		addr = &sin6;
+		alen = sizeof(sin6);
+		break;
+	default:
+		log_error("unknown address family\n");
+		exit(1);
+	}
+
+	if (tcp_md5sig(sd, addr, alen, args->password))
+		return -1;
+
+	return 0;
+}
+
+static int get_ifidx(const char *ifname)
+{
+	struct ifreq ifdata;
+	int sd, rc;
+
+	if (!ifname || *ifname == '\0')
+		return 0;
+
+	memset(&ifdata, 0, sizeof(ifdata));
+
+	strcpy(ifdata.ifr_name, ifname);
+
+	sd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
+	if (sd < 0) {
+		log_err_errno("socket failed");
+		return 0;
+	}
+
+	rc = ioctl(sd, SIOCGIFINDEX, (char *)&ifdata);
+	close(sd);
+	if (rc != 0) {
+		log_err_errno("ioctl(SIOCGIFINDEX) failed");
+		return 0;
+	}
+
+	return ifdata.ifr_ifindex;
+}
+
+static int bind_to_device(int sd, const char *name)
+{
+	int rc;
+
+	rc = setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, name, strlen(name)+1);
+	if (rc < 0)
+		log_err_errno("setsockopt(SO_BINDTODEVICE)");
+
+	return rc;
+}
+
+static int get_bind_to_device(int sd, char *name, size_t len)
+{
+	int rc;
+	socklen_t optlen = len;
+
+	name[0] = '\0';
+	rc = getsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, name, &optlen);
+	if (rc < 0)
+		log_err_errno("setsockopt(SO_BINDTODEVICE)");
+
+	return rc;
+}
+
+static int check_device(int sd, struct sock_args *args)
+{
+	int ifindex = 0;
+	char name[32];
+
+	if (get_bind_to_device(sd, name, sizeof(name)))
+		*name = '\0';
+	else
+		ifindex = get_ifidx(name);
+
+	log_msg("    bound to device %s/%d\n",
+		*name ? name : "<none>", ifindex);
+
+	if (!args->expected_ifindex)
+		return 0;
+
+	if (args->expected_ifindex != ifindex) {
+		log_error("Device index mismatch: expected %d have %d\n",
+			  args->expected_ifindex, ifindex);
+		return 1;
+	}
+
+	log_msg("Device index matches: expected %d have %d\n",
+		args->expected_ifindex, ifindex);
+
+	return 0;
+}
+
+static int set_pktinfo_v4(int sd)
+{
+	int one = 1;
+	int rc;
+
+	rc = setsockopt(sd, SOL_IP, IP_PKTINFO, &one, sizeof(one));
+	if (rc < 0 && rc != -ENOTSUP)
+		log_err_errno("setsockopt(IP_PKTINFO)");
+
+	return rc;
+}
+
+static int set_recvpktinfo_v6(int sd)
+{
+	int one = 1;
+	int rc;
+
+	rc = setsockopt(sd, SOL_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
+	if (rc < 0 && rc != -ENOTSUP)
+		log_err_errno("setsockopt(IPV6_RECVPKTINFO)");
+
+	return rc;
+}
+
+static int set_recverr_v4(int sd)
+{
+	int one = 1;
+	int rc;
+
+	rc = setsockopt(sd, SOL_IP, IP_RECVERR, &one, sizeof(one));
+	if (rc < 0 && rc != -ENOTSUP)
+		log_err_errno("setsockopt(IP_RECVERR)");
+
+	return rc;
+}
+
+static int set_recverr_v6(int sd)
+{
+	int one = 1;
+	int rc;
+
+	rc = setsockopt(sd, SOL_IPV6, IPV6_RECVERR, &one, sizeof(one));
+	if (rc < 0 && rc != -ENOTSUP)
+		log_err_errno("setsockopt(IPV6_RECVERR)");
+
+	return rc;
+}
+
+static int set_unicast_if(int sd, int ifindex, int version)
+{
+	int opt = IP_UNICAST_IF;
+	int level = SOL_IP;
+	int rc;
+
+	ifindex = htonl(ifindex);
+
+	if (version == AF_INET6) {
+		opt = IPV6_UNICAST_IF;
+		level = SOL_IPV6;
+	}
+	rc = setsockopt(sd, level, opt, &ifindex, sizeof(ifindex));
+	if (rc < 0)
+		log_err_errno("setsockopt(IP_UNICAST_IF)");
+
+	return rc;
+}
+
+static int set_multicast_if(int sd, int ifindex)
+{
+	struct ip_mreqn mreq = { .imr_ifindex = ifindex };
+	int rc;
+
+	rc = setsockopt(sd, SOL_IP, IP_MULTICAST_IF, &mreq, sizeof(mreq));
+	if (rc < 0)
+		log_err_errno("setsockopt(IP_MULTICAST_IF)");
+
+	return rc;
+}
+
+static int set_membership(int sd, uint32_t grp, uint32_t addr, const char *dev)
+{
+	uint32_t if_addr = addr;
+	struct ip_mreqn mreq;
+	int rc;
+
+	if (addr == htonl(INADDR_ANY) && !dev) {
+		log_error("Either local address or device needs to be given for multicast membership\n");
+		return -1;
+	}
+
+	mreq.imr_multiaddr.s_addr = grp;
+	mreq.imr_address.s_addr = if_addr;
+	mreq.imr_ifindex = dev ? get_ifidx(dev) : 0;
+
+	rc = setsockopt(sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
+	if (rc < 0) {
+		log_err_errno("setsockopt(IP_ADD_MEMBERSHIP)");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int set_broadcast(int sd)
+{
+	unsigned int one = 1;
+	int rc = 0;
+
+	if (setsockopt(sd, SOL_SOCKET, SO_BROADCAST, &one, sizeof(one)) != 0) {
+		log_err_errno("setsockopt(SO_BROADCAST)");
+		rc = -1;
+	}
+
+	return rc;
+}
+
+static int set_reuseport(int sd)
+{
+	unsigned int one = 1;
+	int rc = 0;
+
+	if (setsockopt(sd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one)) != 0) {
+		log_err_errno("setsockopt(SO_REUSEPORT)");
+		rc = -1;
+	}
+
+	return rc;
+}
+
+static int set_reuseaddr(int sd)
+{
+	unsigned int one = 1;
+	int rc = 0;
+
+	if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) != 0) {
+		log_err_errno("setsockopt(SO_REUSEADDR)");
+		rc = -1;
+	}
+
+	return rc;
+}
+
+static int str_to_uint(const char *str, int min, int max, unsigned int *value)
+{
+	int number;
+	char *end;
+
+	errno = 0;
+	number = (unsigned int) strtoul(str, &end, 0);
+
+	/* entire string should be consumed by conversion
+	 * and value should be between min and max
+	 */
+	if (((*end == '\0') || (*end == '\n')) && (end != str) &&
+	    (errno != ERANGE) && (min <= number) && (number <= max)) {
+		*value = number;
+		return 0;
+	}
+
+	return -1;
+}
+
+static int expected_addr_match(struct sockaddr *sa, void *expected,
+			       const char *desc)
+{
+	char addrstr[64];
+	int rc = 0;
+
+	if (sa->sa_family == AF_INET) {
+		struct sockaddr_in *s = (struct sockaddr_in *) sa;
+		struct in_addr *exp_in = (struct in_addr *) expected;
+
+		if (s->sin_addr.s_addr != exp_in->s_addr) {
+			log_error("%s address does not match expected %s",
+				  desc,
+				  inet_ntop(AF_INET, exp_in,
+					    addrstr, sizeof(addrstr)));
+			rc = 1;
+		}
+	} else if (sa->sa_family == AF_INET6) {
+		struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
+		struct in6_addr *exp_in = (struct in6_addr *) expected;
+
+		if (memcmp(&s6->sin6_addr, exp_in, sizeof(*exp_in))) {
+			log_error("%s address does not match expected %s",
+				  desc,
+				  inet_ntop(AF_INET6, exp_in,
+					    addrstr, sizeof(addrstr)));
+			rc = 1;
+		}
+	} else {
+		log_error("%s address does not match expected - unknown family",
+			  desc);
+		rc = 1;
+	}
+
+	if (!rc)
+		log_msg("%s address matches expected\n", desc);
+
+	return rc;
+}
+
+static int show_sockstat(int sd, struct sock_args *args)
+{
+	struct sockaddr_in6 local_addr, remote_addr;
+	socklen_t alen = sizeof(local_addr);
+	struct sockaddr *sa;
+	const char *desc;
+	int rc = 0;
+
+	desc = server_mode ? "server local:" : "client local:";
+	sa = (struct sockaddr *) &local_addr;
+	if (getsockname(sd, sa, &alen) == 0) {
+		log_address(desc, sa);
+
+		if (args->has_expected_laddr) {
+			rc = expected_addr_match(sa, &args->expected_laddr,
+						 "local");
+		}
+	} else {
+		log_err_errno("getsockname failed");
+	}
+
+	sa = (struct sockaddr *) &remote_addr;
+	desc = server_mode ? "server peer:" : "client peer:";
+	if (getpeername(sd, sa, &alen) == 0) {
+		log_address(desc, sa);
+
+		if (args->has_expected_raddr) {
+			rc |= expected_addr_match(sa, &args->expected_raddr,
+						 "remote");
+		}
+	} else {
+		log_err_errno("getpeername failed");
+	}
+
+	return rc;
+}
+
+static int get_index_from_cmsg(struct msghdr *m)
+{
+	struct cmsghdr *cm;
+	int ifindex = 0;
+	char buf[64];
+
+	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(m);
+	     m->msg_controllen != 0 && cm;
+	     cm = (struct cmsghdr *)CMSG_NXTHDR(m, cm)) {
+
+		if (cm->cmsg_level == SOL_IP &&
+		    cm->cmsg_type == IP_PKTINFO) {
+			struct in_pktinfo *pi;
+
+			pi = (struct in_pktinfo *)(CMSG_DATA(cm));
+			inet_ntop(AF_INET, &pi->ipi_addr, buf, sizeof(buf));
+			ifindex = pi->ipi_ifindex;
+		} else if (cm->cmsg_level == SOL_IPV6 &&
+			   cm->cmsg_type == IPV6_PKTINFO) {
+			struct in6_pktinfo *pi6;
+
+			pi6 = (struct in6_pktinfo *)(CMSG_DATA(cm));
+			inet_ntop(AF_INET6, &pi6->ipi6_addr, buf, sizeof(buf));
+			ifindex = pi6->ipi6_ifindex;
+		}
+	}
+
+	if (ifindex) {
+		log_msg("    pktinfo: ifindex %d dest addr %s\n",
+			ifindex, buf);
+	}
+	return ifindex;
+}
+
+static int send_msg_no_cmsg(int sd, void *addr, socklen_t alen)
+{
+	int err;
+
+again:
+	err = sendto(sd, msg, msglen, 0, addr, alen);
+	if (err < 0) {
+		if (errno == EACCES && try_broadcast) {
+			try_broadcast = 0;
+			if (!set_broadcast(sd))
+				goto again;
+			errno = EACCES;
+		}
+
+		log_err_errno("sendto failed");
+		return 1;
+	}
+
+	return 0;
+}
+
+static int send_msg_cmsg(int sd, void *addr, socklen_t alen,
+			 int ifindex, int version)
+{
+	unsigned char cmsgbuf[64];
+	struct iovec iov[2];
+	struct cmsghdr *cm;
+	struct msghdr m;
+	int err;
+
+	iov[0].iov_base = msg;
+	iov[0].iov_len = msglen;
+	m.msg_iov = iov;
+	m.msg_iovlen = 1;
+	m.msg_name = (caddr_t)addr;
+	m.msg_namelen = alen;
+
+	memset(cmsgbuf, 0, sizeof(cmsgbuf));
+	cm = (struct cmsghdr *)cmsgbuf;
+	m.msg_control = (caddr_t)cm;
+
+	if (version == AF_INET) {
+		struct in_pktinfo *pi;
+
+		cm->cmsg_level = SOL_IP;
+		cm->cmsg_type = IP_PKTINFO;
+		cm->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
+		pi = (struct in_pktinfo *)(CMSG_DATA(cm));
+		pi->ipi_ifindex = ifindex;
+
+		m.msg_controllen = cm->cmsg_len;
+
+	} else if (version == AF_INET6) {
+		struct in6_pktinfo *pi6;
+
+		cm->cmsg_level = SOL_IPV6;
+		cm->cmsg_type = IPV6_PKTINFO;
+		cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
+
+		pi6 = (struct in6_pktinfo *)(CMSG_DATA(cm));
+		pi6->ipi6_ifindex = ifindex;
+
+		m.msg_controllen = cm->cmsg_len;
+	}
+
+again:
+	err = sendmsg(sd, &m, 0);
+	if (err < 0) {
+		if (errno == EACCES && try_broadcast) {
+			try_broadcast = 0;
+			if (!set_broadcast(sd))
+				goto again;
+			errno = EACCES;
+		}
+
+		log_err_errno("sendmsg failed");
+		return 1;
+	}
+
+	return 0;
+}
+
+
+static int send_msg(int sd, void *addr, socklen_t alen, struct sock_args *args)
+{
+	if (args->type == SOCK_STREAM) {
+		if (write(sd, msg, msglen) < 0) {
+			log_err_errno("write failed sending msg to peer");
+			return 1;
+		}
+	} else if (args->ifindex && args->use_cmsg) {
+		if (send_msg_cmsg(sd, addr, alen, args->ifindex, args->version))
+			return 1;
+	} else {
+		if (send_msg_no_cmsg(sd, addr, alen))
+			return 1;
+	}
+
+	log_msg("Sent message:\n");
+	log_msg("    %.24s%s\n", msg, msglen > 24 ? " ..." : "");
+
+	return 0;
+}
+
+static int socket_read_dgram(int sd, struct sock_args *args)
+{
+	unsigned char addr[sizeof(struct sockaddr_in6)];
+	struct sockaddr *sa = (struct sockaddr *) addr;
+	socklen_t alen = sizeof(addr);
+	struct iovec iov[2];
+	struct msghdr m = {
+		.msg_name = (caddr_t)addr,
+		.msg_namelen = alen,
+		.msg_iov = iov,
+		.msg_iovlen = 1,
+	};
+	unsigned char cmsgbuf[256];
+	struct cmsghdr *cm = (struct cmsghdr *)cmsgbuf;
+	char buf[16*1024];
+	int ifindex;
+	int len;
+
+	iov[0].iov_base = (caddr_t)buf;
+	iov[0].iov_len = sizeof(buf);
+
+	memset(cmsgbuf, 0, sizeof(cmsgbuf));
+	m.msg_control = (caddr_t)cm;
+	m.msg_controllen = sizeof(cmsgbuf);
+
+	len = recvmsg(sd, &m, 0);
+	if (len == 0) {
+		log_msg("peer closed connection.\n");
+		return 0;
+	} else if (len < 0) {
+		log_msg("failed to read message: %d: %s\n",
+			errno, strerror(errno));
+		return -1;
+	}
+
+	buf[len] = '\0';
+
+	log_address("Message from:", sa);
+	log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
+
+	ifindex = get_index_from_cmsg(&m);
+	if (args->expected_ifindex) {
+		if (args->expected_ifindex != ifindex) {
+			log_error("Device index mismatch: expected %d have %d\n",
+				  args->expected_ifindex, ifindex);
+			return -1;
+		}
+		log_msg("Device index matches: expected %d have %d\n",
+			args->expected_ifindex, ifindex);
+	}
+
+	if (!interactive && server_mode) {
+		if (sa->sa_family == AF_INET6) {
+			struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
+			struct in6_addr *in6 = &s6->sin6_addr;
+
+			if (IN6_IS_ADDR_V4MAPPED(in6)) {
+				const uint32_t *pa = (uint32_t *) &in6->s6_addr;
+				struct in_addr in4;
+				struct sockaddr_in *sin;
+
+				sin = (struct sockaddr_in *) addr;
+				pa += 3;
+				in4.s_addr = *pa;
+				sin->sin_addr = in4;
+				sin->sin_family = AF_INET;
+				if (send_msg_cmsg(sd, addr, alen,
+						  ifindex, AF_INET) < 0)
+					goto out_err;
+			}
+		}
+again:
+		iov[0].iov_len = len;
+
+		if (args->version == AF_INET6) {
+			struct sockaddr_in6 *s6 = (struct sockaddr_in6 *) sa;
+
+			if (args->dev) {
+				/* avoid PKTINFO conflicts with bindtodev */
+				if (sendto(sd, buf, len, 0,
+					   (void *) addr, alen) < 0)
+					goto out_err;
+			} else {
+				/* kernel is allowing scope_id to be set to VRF
+				 * index for LLA. for sends to global address
+				 * reset scope id
+				 */
+				s6->sin6_scope_id = ifindex;
+				if (sendmsg(sd, &m, 0) < 0)
+					goto out_err;
+			}
+		} else {
+			int err;
+
+			err = sendmsg(sd, &m, 0);
+			if (err < 0) {
+				if (errno == EACCES && try_broadcast) {
+					try_broadcast = 0;
+					if (!set_broadcast(sd))
+						goto again;
+					errno = EACCES;
+				}
+				goto out_err;
+			}
+		}
+		log_msg("Sent message:\n");
+		log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
+	}
+
+	return 1;
+out_err:
+	log_err_errno("failed to send msg to peer");
+	return -1;
+}
+
+static int socket_read_stream(int sd)
+{
+	char buf[1024];
+	int len;
+
+	len = read(sd, buf, sizeof(buf)-1);
+	if (len == 0) {
+		log_msg("client closed connection.\n");
+		return 0;
+	} else if (len < 0) {
+		log_msg("failed to read message\n");
+		return -1;
+	}
+
+	buf[len] = '\0';
+	log_msg("Incoming message:\n");
+	log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
+
+	if (!interactive && server_mode) {
+		if (write(sd, buf, len) < 0) {
+			log_err_errno("failed to send buf");
+			return -1;
+		}
+		log_msg("Sent message:\n");
+		log_msg("     %.24s%s\n", buf, len > 24 ? " ..." : "");
+	}
+
+	return 1;
+}
+
+static int socket_read(int sd, struct sock_args *args)
+{
+	if (args->type == SOCK_STREAM)
+		return socket_read_stream(sd);
+
+	return socket_read_dgram(sd, args);
+}
+
+static int stdin_to_socket(int sd, int type, void *addr, socklen_t alen)
+{
+	char buf[1024];
+	int len;
+
+	if (fgets(buf, sizeof(buf), stdin) == NULL)
+		return 0;
+
+	len = strlen(buf);
+	if (type == SOCK_STREAM) {
+		if (write(sd, buf, len) < 0) {
+			log_err_errno("failed to send buf");
+			return -1;
+		}
+	} else {
+		int err;
+
+again:
+		err = sendto(sd, buf, len, 0, addr, alen);
+		if (err < 0) {
+			if (errno == EACCES && try_broadcast) {
+				try_broadcast = 0;
+				if (!set_broadcast(sd))
+					goto again;
+				errno = EACCES;
+			}
+			log_err_errno("failed to send msg to peer");
+			return -1;
+		}
+	}
+	log_msg("Sent message:\n");
+	log_msg("    %.24s%s\n", buf, len > 24 ? " ..." : "");
+
+	return 1;
+}
+
+static void set_recv_attr(int sd, int version)
+{
+	if (version == AF_INET6) {
+		set_recvpktinfo_v6(sd);
+		set_recverr_v6(sd);
+	} else {
+		set_pktinfo_v4(sd);
+		set_recverr_v4(sd);
+	}
+}
+
+static int msg_loop(int client, int sd, void *addr, socklen_t alen,
+		    struct sock_args *args)
+{
+	struct timeval timeout = { .tv_sec = prog_timeout }, *ptval = NULL;
+	fd_set rfds;
+	int nfds;
+	int rc;
+
+	if (args->type != SOCK_STREAM)
+		set_recv_attr(sd, args->version);
+
+	if (msg) {
+		msglen = strlen(msg);
+
+		/* client sends first message */
+		if (client) {
+			if (send_msg(sd, addr, alen, args))
+				return 1;
+		}
+		if (!interactive) {
+			ptval = &timeout;
+			if (!prog_timeout)
+				timeout.tv_sec = 5;
+		}
+	}
+
+	nfds = interactive ? MAX(fileno(stdin), sd)  + 1 : sd + 1;
+	while (1) {
+		FD_ZERO(&rfds);
+		FD_SET(sd, &rfds);
+		if (interactive)
+			FD_SET(fileno(stdin), &rfds);
+
+		rc = select(nfds, &rfds, NULL, NULL, ptval);
+		if (rc < 0) {
+			if (errno == EINTR)
+				continue;
+
+			rc = 1;
+			log_err_errno("select failed");
+			break;
+		} else if (rc == 0) {
+			log_error("Timed out waiting for response\n");
+			rc = 2;
+			break;
+		}
+
+		if (FD_ISSET(sd, &rfds)) {
+			rc = socket_read(sd, args);
+			if (rc < 0) {
+				rc = 1;
+				break;
+			}
+			if (rc == 0)
+				break;
+		}
+
+		rc = 0;
+
+		if (FD_ISSET(fileno(stdin), &rfds)) {
+			if (stdin_to_socket(sd, args->type, addr, alen) <= 0)
+				break;
+		}
+
+		if (interactive)
+			continue;
+
+		if (iter != -1) {
+			--iter;
+			if (iter == 0)
+				break;
+		}
+
+		log_msg("Going into quiet mode\n");
+		quiet = 1;
+
+		if (client) {
+			if (send_msg(sd, addr, alen, args)) {
+				rc = 1;
+				break;
+			}
+		}
+	}
+
+	return rc;
+}
+
+static int msock_init(struct sock_args *args, int server)
+{
+	uint32_t if_addr = htonl(INADDR_ANY);
+	struct sockaddr_in laddr = {
+		.sin_family = AF_INET,
+		.sin_port = htons(args->port),
+	};
+	int one = 1;
+	int sd;
+
+	if (!server && args->has_local_ip)
+		if_addr = args->local_addr.in.s_addr;
+
+	sd = socket(PF_INET, SOCK_DGRAM, 0);
+	if (sd < 0) {
+		log_err_errno("socket");
+		return -1;
+	}
+
+	if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR,
+		       (char *)&one, sizeof(one)) < 0) {
+		log_err_errno("Setting SO_REUSEADDR error");
+		goto out_err;
+	}
+
+	if (setsockopt(sd, SOL_SOCKET, SO_BROADCAST,
+		       (char *)&one, sizeof(one)) < 0)
+		log_err_errno("Setting SO_BROADCAST error");
+
+	if (args->dev && bind_to_device(sd, args->dev) != 0)
+		goto out_err;
+	else if (args->use_setsockopt &&
+		 set_multicast_if(sd, args->ifindex))
+		goto out_err;
+
+	laddr.sin_addr.s_addr = if_addr;
+
+	if (bind(sd, (struct sockaddr *) &laddr, sizeof(laddr)) < 0) {
+		log_err_errno("bind failed");
+		goto out_err;
+	}
+
+	if (server &&
+	    set_membership(sd, args->grp.s_addr,
+			   args->local_addr.in.s_addr, args->dev))
+		goto out_err;
+
+	return sd;
+out_err:
+	close(sd);
+	return -1;
+}
+
+static int msock_server(struct sock_args *args)
+{
+	return msock_init(args, 1);
+}
+
+static int msock_client(struct sock_args *args)
+{
+	return msock_init(args, 0);
+}
+
+static int bind_socket(int sd, struct sock_args *args)
+{
+	struct sockaddr_in serv_addr = {
+		.sin_family = AF_INET,
+	};
+	struct sockaddr_in6 serv6_addr = {
+		.sin6_family = AF_INET6,
+	};
+	void *addr;
+	socklen_t alen;
+
+	if (!args->has_local_ip && args->type == SOCK_RAW)
+		return 0;
+
+	switch (args->version) {
+	case AF_INET:
+		serv_addr.sin_port = htons(args->port);
+		serv_addr.sin_addr = args->local_addr.in;
+		addr = &serv_addr;
+		alen = sizeof(serv_addr);
+		break;
+
+	case AF_INET6:
+		serv6_addr.sin6_port = htons(args->port);
+		serv6_addr.sin6_addr = args->local_addr.in6;
+		addr = &serv6_addr;
+		alen = sizeof(serv6_addr);
+		break;
+
+	default:
+		log_error("Invalid address family\n");
+		return -1;
+	}
+
+	if (bind(sd, addr, alen) < 0) {
+		log_err_errno("error binding socket");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int lsock_init(struct sock_args *args)
+{
+	long flags;
+	int sd;
+
+	sd = socket(args->version, args->type, args->protocol);
+	if (sd < 0) {
+		log_err_errno("Error opening socket");
+		return  -1;
+	}
+
+	if (set_reuseaddr(sd) != 0)
+		goto err;
+
+	if (set_reuseport(sd) != 0)
+		goto err;
+
+	if (args->dev && bind_to_device(sd, args->dev) != 0)
+		goto err;
+	else if (args->use_setsockopt &&
+		 set_unicast_if(sd, args->ifindex, args->version))
+		goto err;
+
+	if (bind_socket(sd, args))
+		goto err;
+
+	if (args->bind_test_only)
+		goto out;
+
+	if (args->type == SOCK_STREAM && listen(sd, 1) < 0) {
+		log_err_errno("listen failed");
+		goto err;
+	}
+
+	flags = fcntl(sd, F_GETFL);
+	if ((flags < 0) || (fcntl(sd, F_SETFL, flags|O_NONBLOCK) < 0)) {
+		log_err_errno("Failed to set non-blocking option");
+		goto err;
+	}
+
+	if (fcntl(sd, F_SETFD, FD_CLOEXEC) < 0)
+		log_err_errno("Failed to set close-on-exec flag");
+
+out:
+	return sd;
+
+err:
+	close(sd);
+	return -1;
+}
+
+static int do_server(struct sock_args *args)
+{
+	struct timeval timeout = { .tv_sec = prog_timeout }, *ptval = NULL;
+	unsigned char addr[sizeof(struct sockaddr_in6)] = {};
+	socklen_t alen = sizeof(addr);
+	int lsd, csd = -1;
+
+	fd_set rfds;
+	int rc;
+
+	if (prog_timeout)
+		ptval = &timeout;
+
+	if (args->has_grp)
+		lsd = msock_server(args);
+	else
+		lsd = lsock_init(args);
+
+	if (lsd < 0)
+		return 1;
+
+	if (args->bind_test_only) {
+		close(lsd);
+		return 0;
+	}
+
+	if (args->type != SOCK_STREAM) {
+		rc = msg_loop(0, lsd, (void *) addr, alen, args);
+		close(lsd);
+		return rc;
+	}
+
+	if (args->password && tcp_md5_remote(lsd, args)) {
+		close(lsd);
+		return -1;
+	}
+
+	while (1) {
+		log_msg("\n");
+		log_msg("waiting for client connection.\n");
+		FD_ZERO(&rfds);
+		FD_SET(lsd, &rfds);
+
+		rc = select(lsd+1, &rfds, NULL, NULL, ptval);
+		if (rc == 0) {
+			rc = 2;
+			break;
+		}
+
+		if (rc < 0) {
+			if (errno == EINTR)
+				continue;
+
+			log_err_errno("select failed");
+			break;
+		}
+
+		if (FD_ISSET(lsd, &rfds)) {
+
+			csd = accept(lsd, (void *) addr, &alen);
+			if (csd < 0) {
+				log_err_errno("accept failed");
+				break;
+			}
+
+			rc = show_sockstat(csd, args);
+			if (rc)
+				break;
+
+			rc = check_device(csd, args);
+			if (rc)
+				break;
+		}
+
+		rc = msg_loop(0, csd, (void *) addr, alen, args);
+		close(csd);
+
+		if (!interactive)
+			break;
+	}
+
+	close(lsd);
+
+	return rc;
+}
+
+static int wait_for_connect(int sd)
+{
+	struct timeval _tv = { .tv_sec = prog_timeout }, *tv = NULL;
+	fd_set wfd;
+	int val = 0, sz = sizeof(val);
+	int rc;
+
+	FD_ZERO(&wfd);
+	FD_SET(sd, &wfd);
+
+	if (prog_timeout)
+		tv = &_tv;
+
+	rc = select(FD_SETSIZE, NULL, &wfd, NULL, tv);
+	if (rc == 0) {
+		log_error("connect timed out\n");
+		return -2;
+	} else if (rc < 0) {
+		log_err_errno("select failed");
+		return -3;
+	}
+
+	if (getsockopt(sd, SOL_SOCKET, SO_ERROR, &val, (socklen_t *)&sz) < 0) {
+		log_err_errno("getsockopt(SO_ERROR) failed");
+		return -4;
+	}
+
+	if (val != 0) {
+		log_error("connect failed: %d: %s\n", val, strerror(val));
+		return -1;
+	}
+
+	return 0;
+}
+
+static int connectsock(void *addr, socklen_t alen, struct sock_args *args)
+{
+	int sd, rc = -1;
+	long flags;
+
+	sd = socket(args->version, args->type, args->protocol);
+	if (sd < 0) {
+		log_err_errno("Failed to create socket");
+		return -1;
+	}
+
+	flags = fcntl(sd, F_GETFL);
+	if ((flags < 0) || (fcntl(sd, F_SETFL, flags|O_NONBLOCK) < 0)) {
+		log_err_errno("Failed to set non-blocking option");
+		goto err;
+	}
+
+	if (set_reuseport(sd) != 0)
+		goto err;
+
+	if (args->dev && bind_to_device(sd, args->dev) != 0)
+		goto err;
+	else if (args->use_setsockopt &&
+		 set_unicast_if(sd, args->ifindex, args->version))
+		goto err;
+
+	if (args->has_local_ip && bind_socket(sd, args))
+		goto err;
+
+	if (args->type != SOCK_STREAM)
+		goto out;
+
+	if (args->password && tcp_md5sig(sd, addr, alen, args->password))
+		goto err;
+
+	if (args->bind_test_only)
+		goto out;
+
+	if (connect(sd, addr, alen) < 0) {
+		if (errno != EINPROGRESS) {
+			log_err_errno("Failed to connect to remote host");
+			rc = -1;
+			goto err;
+		}
+		rc = wait_for_connect(sd);
+		if (rc < 0)
+			goto err;
+	}
+out:
+	return sd;
+
+err:
+	close(sd);
+	return rc;
+}
+
+static int do_client(struct sock_args *args)
+{
+	struct sockaddr_in sin = {
+		.sin_family = AF_INET,
+	};
+	struct sockaddr_in6 sin6 = {
+		.sin6_family = AF_INET6,
+	};
+	void *addr;
+	int alen;
+	int rc = 0;
+	int sd;
+
+	if (!args->has_remote_ip && !args->has_grp) {
+		fprintf(stderr, "remote IP or multicast group not given\n");
+		return 1;
+	}
+
+	switch (args->version) {
+	case AF_INET:
+		sin.sin_port = htons(args->port);
+		if (args->has_grp)
+			sin.sin_addr = args->grp;
+		else
+			sin.sin_addr = args->remote_addr.in;
+		addr = &sin;
+		alen = sizeof(sin);
+		break;
+	case AF_INET6:
+		sin6.sin6_port = htons(args->port);
+		sin6.sin6_addr = args->remote_addr.in6;
+		sin6.sin6_scope_id = args->scope_id;
+		addr = &sin6;
+		alen = sizeof(sin6);
+		break;
+	}
+
+	if (args->has_grp)
+		sd = msock_client(args);
+	else
+		sd = connectsock(addr, alen, args);
+
+	if (sd < 0)
+		return -sd;
+
+	if (args->bind_test_only)
+		goto out;
+
+	if (args->type == SOCK_STREAM) {
+		rc = show_sockstat(sd, args);
+		if (rc != 0)
+			goto out;
+	}
+
+	rc = msg_loop(1, sd, addr, alen, args);
+
+out:
+	close(sd);
+
+	return rc;
+}
+
+enum addr_type {
+	ADDR_TYPE_LOCAL,
+	ADDR_TYPE_REMOTE,
+	ADDR_TYPE_MCAST,
+	ADDR_TYPE_EXPECTED_LOCAL,
+	ADDR_TYPE_EXPECTED_REMOTE,
+};
+
+static int convert_addr(struct sock_args *args, const char *_str,
+			enum addr_type atype)
+{
+	int family = args->version;
+	struct in6_addr *in6;
+	struct in_addr  *in;
+	const char *desc;
+	char *str, *dev;
+	void *addr;
+	int rc = 0;
+
+	str = strdup(_str);
+	if (!str)
+		return -ENOMEM;
+
+	switch (atype) {
+	case ADDR_TYPE_LOCAL:
+		desc = "local";
+		addr = &args->local_addr;
+		break;
+	case ADDR_TYPE_REMOTE:
+		desc = "remote";
+		addr = &args->remote_addr;
+		break;
+	case ADDR_TYPE_MCAST:
+		desc = "mcast grp";
+		addr = &args->grp;
+		break;
+	case ADDR_TYPE_EXPECTED_LOCAL:
+		desc = "expected local";
+		addr = &args->expected_laddr;
+		break;
+	case ADDR_TYPE_EXPECTED_REMOTE:
+		desc = "expected remote";
+		addr = &args->expected_raddr;
+		break;
+	default:
+		log_error("unknown address type");
+		exit(1);
+	}
+
+	switch (family) {
+	case AF_INET:
+		in  = (struct in_addr *) addr;
+		if (str) {
+			if (inet_pton(AF_INET, str, in) == 0) {
+				log_error("Invalid %s IP address\n", desc);
+				rc = -1;
+				goto out;
+			}
+		} else {
+			in->s_addr = htonl(INADDR_ANY);
+		}
+		break;
+
+	case AF_INET6:
+		dev = strchr(str, '%');
+		if (dev) {
+			*dev = '\0';
+			dev++;
+		}
+
+		in6 = (struct in6_addr *) addr;
+		if (str) {
+			if (inet_pton(AF_INET6, str, in6) == 0) {
+				log_error("Invalid %s IPv6 address\n", desc);
+				rc = -1;
+				goto out;
+			}
+		} else {
+			*in6 = in6addr_any;
+		}
+		if (dev) {
+			args->scope_id = get_ifidx(dev);
+			if (args->scope_id < 0) {
+				log_error("Invalid scope on %s IPv6 address\n",
+					  desc);
+				rc = -1;
+				goto out;
+			}
+		}
+		break;
+
+	default:
+		log_error("Invalid address family\n");
+	}
+
+out:
+	free(str);
+	return rc;
+}
+
+static char *random_msg(int len)
+{
+	int i, n = 0, olen = len + 1;
+	char *m;
+
+	if (len <= 0)
+		return NULL;
+
+	m = malloc(olen);
+	if (!m)
+		return NULL;
+
+	while (len > 26) {
+		i = snprintf(m + n, olen - n, "%.26s",
+			     "abcdefghijklmnopqrstuvwxyz");
+		n += i;
+		len -= i;
+	}
+	i = snprintf(m + n, olen - n, "%.*s", len,
+		     "abcdefghijklmnopqrstuvwxyz");
+	return m;
+}
+
+#define GETOPT_STR  "sr:l:p:t:g:P:DRn:M:d:SCi6L:0:1:2:Fbq"
+
+static void print_usage(char *prog)
+{
+	printf(
+	"usage: %s OPTS\n"
+	"Required:\n"
+	"    -r addr       remote address to connect to (client mode only)\n"
+	"    -p port       port to connect to (client mode)/listen on (server mode)\n"
+	"                  (default: %d)\n"
+	"    -s            server mode (default: client mode)\n"
+	"    -t            timeout seconds (default: none)\n"
+	"\n"
+	"Optional:\n"
+	"    -F            Restart server loop\n"
+	"    -6            IPv6 (default is IPv4)\n"
+	"    -P proto      protocol for socket: icmp, ospf (default: none)\n"
+	"    -D|R          datagram (D) / raw (R) socket (default stream)\n"
+	"    -l addr       local address to bind to\n"
+	"\n"
+	"    -d dev        bind socket to given device name\n"
+	"    -S            use setsockopt (IP_UNICAST_IF or IP_MULTICAST_IF)\n"
+	"                  to set device binding\n"
+	"    -C            use cmsg and IP_PKTINFO to specify device binding\n"
+	"\n"
+	"    -L len        send random message of given length\n"
+	"    -n num        number of times to send message\n"
+	"\n"
+	"    -M password   use MD5 sum protection\n"
+	"    -g grp        multicast group (e.g., 239.1.1.1)\n"
+	"    -i            interactive mode (default is echo and terminate)\n"
+	"\n"
+	"    -0 addr       Expected local address\n"
+	"    -1 addr       Expected remote address\n"
+	"    -2 dev        Expected device name (or index) to receive packet\n"
+	"\n"
+	"    -b            Bind test only.\n"
+	"    -q            Be quiet. Run test without printing anything.\n"
+	, prog, DEFAULT_PORT);
+}
+
+int main(int argc, char *argv[])
+{
+	struct sock_args args = {
+		.version = AF_INET,
+		.type    = SOCK_STREAM,
+		.port    = DEFAULT_PORT,
+	};
+	struct protoent *pe;
+	unsigned int tmp;
+	int forever = 0;
+
+	/* process inputs */
+	extern char *optarg;
+	int rc = 0;
+
+	/*
+	 * process input args
+	 */
+
+	while ((rc = getopt(argc, argv, GETOPT_STR)) != -1) {
+		switch (rc) {
+		case 's':
+			server_mode = 1;
+			break;
+		case 'F':
+			forever = 1;
+			break;
+		case 'l':
+			args.has_local_ip = 1;
+			if (convert_addr(&args, optarg, ADDR_TYPE_LOCAL) < 0)
+				return 1;
+			break;
+		case 'r':
+			args.has_remote_ip = 1;
+			if (convert_addr(&args, optarg, ADDR_TYPE_REMOTE) < 0)
+				return 1;
+			break;
+		case 'p':
+			if (str_to_uint(optarg, 1, 65535, &tmp) != 0) {
+				fprintf(stderr, "Invalid port\n");
+				return 1;
+			}
+			args.port = (unsigned short) tmp;
+			break;
+		case 't':
+			if (str_to_uint(optarg, 0, INT_MAX,
+					&prog_timeout) != 0) {
+				fprintf(stderr, "Invalid timeout\n");
+				return 1;
+			}
+			break;
+		case 'D':
+			args.type = SOCK_DGRAM;
+			break;
+		case 'R':
+			args.type = SOCK_RAW;
+			args.port = 0;
+			break;
+		case 'P':
+			pe = getprotobyname(optarg);
+			if (pe) {
+				args.protocol = pe->p_proto;
+			} else {
+				if (str_to_uint(optarg, 0, 0xffff, &tmp) != 0) {
+					fprintf(stderr, "Invalid potocol\n");
+					return 1;
+				}
+				args.protocol = tmp;
+			}
+			break;
+		case 'n':
+			iter = atoi(optarg);
+			break;
+		case 'L':
+			msg = random_msg(atoi(optarg));
+			break;
+		case 'M':
+			args.password = optarg;
+			break;
+		case 'S':
+			args.use_setsockopt = 1;
+			break;
+		case 'C':
+			args.use_cmsg = 1;
+			break;
+		case 'd':
+			args.dev = optarg;
+			args.ifindex = get_ifidx(optarg);
+			if (args.ifindex < 0) {
+				fprintf(stderr, "Invalid device name\n");
+				return 1;
+			}
+			break;
+		case 'i':
+			interactive = 1;
+			break;
+		case 'g':
+			args.has_grp = 1;
+			if (convert_addr(&args, optarg, ADDR_TYPE_MCAST) < 0)
+				return 1;
+			args.type = SOCK_DGRAM;
+			break;
+		case '6':
+			args.version = AF_INET6;
+			break;
+		case 'b':
+			args.bind_test_only = 1;
+			break;
+		case '0':
+			args.has_expected_laddr = 1;
+			if (convert_addr(&args, optarg,
+					 ADDR_TYPE_EXPECTED_LOCAL))
+				return 1;
+			break;
+		case '1':
+			args.has_expected_raddr = 1;
+			if (convert_addr(&args, optarg,
+					 ADDR_TYPE_EXPECTED_REMOTE))
+				return 1;
+
+			break;
+		case '2':
+			if (str_to_uint(optarg, 0, 0x7ffffff, &tmp) != 0) {
+				tmp = get_ifidx(optarg);
+				if (tmp < 0) {
+					fprintf(stderr,
+						"Invalid device index\n");
+					return 1;
+				}
+			}
+			args.expected_ifindex = (int)tmp;
+			break;
+		case 'q':
+			quiet = 1;
+			break;
+		default:
+			print_usage(argv[0]);
+			return 1;
+		}
+	}
+
+	if (args.password &&
+	    (!args.has_remote_ip || args.type != SOCK_STREAM)) {
+		log_error("MD5 passwords apply to TCP only and require a remote ip for the password\n");
+		return 1;
+	}
+
+	if ((args.use_setsockopt || args.use_cmsg) && !args.ifindex) {
+		fprintf(stderr, "Device binding not specified\n");
+		return 1;
+	}
+	if (args.use_setsockopt || args.use_cmsg)
+		args.dev = NULL;
+
+	if (iter == 0) {
+		fprintf(stderr, "Invalid number of messages to send\n");
+		return 1;
+	}
+
+	if (args.type == SOCK_STREAM && !args.protocol)
+		args.protocol = IPPROTO_TCP;
+	if (args.type == SOCK_DGRAM && !args.protocol)
+		args.protocol = IPPROTO_UDP;
+
+	if ((args.type == SOCK_STREAM || args.type == SOCK_DGRAM) &&
+	     args.port == 0) {
+		fprintf(stderr, "Invalid port number\n");
+		return 1;
+	}
+
+	if (!server_mode && !args.has_grp &&
+	    !args.has_remote_ip && !args.has_local_ip) {
+		fprintf(stderr,
+			"Local (server mode) or remote IP (client IP) required\n");
+		return 1;
+	}
+
+	if (interactive) {
+		prog_timeout = 0;
+		msg = NULL;
+	}
+
+	if (server_mode) {
+		do {
+			rc = do_server(&args);
+		} while (forever);
+
+		return rc;
+	}
+	return do_client(&args);
+}